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New Member

CBWFQ on ADSL Cisco routers doesn't work without LFI


I'm trying the conf found in the following URL to work:

For testing, I send a huge message via SMTP. This traffic has 128k reserved in the policy map.

Meanwhile, I send a huge message via webmail over the DSL so the uplink gets full. I don't reserve banwidth for that. When this starts, the other traffic slow down the speed to 40kbps aprox (so reservation does not work) and I see how the ATM interface reports output drops.

When I query the state of the policy map applied to the interface (show policy-map interface dialer 1) I see matches over the class map but no matches over the queue (pkts matched/bytes matched).

If I query the Dialer queue (show queue dialer 1) I see it's always empty but if I query the ATM queue I can see the wfq queue with both conversations.

If you try similar confs you'll see the same.

This router is connected to a ISP so can't negotiate the LFI feature, but I think this would be independent of the CBWFQ.

I've noticed too that the queueing mechanism in the Dialer interface (weighted fair) is not cloned to the Virtual-Access. I've tried to upgrade the IOS too to the latest 11.3T version but still not working.

Instead, I've tried it with a Virtual Template and it works, but I have problems with the negotiated IP address and the NAT feature.

I've found the following technote, where you can read: ...the DSL interfaces do not support service policies that apply fancy queueing since these interfaces do not implement the "back-pressure algorithm" necessary to signal that excess packets should be queued by the Layer 3 (L3) queueing system.

I've found some other posts with similar problems.

Could be probably a bug or an error configuration or a limited feature?

Many thanks.


Re: CBWFQ on ADSL Cisco routers doesn't work without LFI

Check the IOS version your using and I guess 12.2(8)YM should support this.

New Member

Re: CBWFQ on ADSL Cisco routers doesn't work without LFI

I'll test it.


New Member

Re: CBWFQ on ADSL Cisco routers doesn't work without LFI

Sorry but I havent found the IOS you mention in IOS downloads.

Also, all 12.2 IOS releases for 837 are deferred.


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